Marco ... I read your post on rGB / CMYK conversion and I'm looking for the answer you are ... I work through a print broker that prints CMYK and the only thing he can tell me is that they print CMYK and on sheet fed coated. So my question is di turn everything to CMYK on my monitor and change to sheet fed coated in the settings?

>I work through a print broker that prints CMYK and the only thing he can tell me is that they print CMYK and on sheet fed coated.

Well, yes, print is always CMYK. As for "sheetfed coated", I would assume that they intend a color space like the one described by the U.S. Sheetfed Coated v2 profile (though it could possibly be the GRACoL2006_Coated1v2 profile). You may want to ask them to confirm one or the other, to be safer.

>So my question is di turn everything to CMYK on my monitor and change to sheet fed coated in the settings?

To make sure I understand your question, I think you are asking me whether you should turn your image file(s) to a chosen CMYK output profile. Yes and no. You should do your color and tonal correction work
b in RGB
, and convert to the intended CMYK output profile
b only as a last step
, just before you deliver the files to the print provider or the prepress specialists.

Do
b not
convert your files to the intended CMYK output profile in the beginning and correct them in CMYK. Do not do that. That is not the most desirable way to work.

The default working spaces in Photoshop's Color Settings are important, but not essential. Yes, you should set the default RGB profile to AdobeRGB (if not ProPhoto RGB, though you may wish to hold off on that one until you have more experience with the application), and the CMYK default profile to U.S. Sheetfed Coated v2.

But, as long as your chosen color management policies are to "Preserve Embedded Profiles", and as long as the image files you work on are tagged with the appropriate profile, then the default profile in Color Settings is no longer relevant.